3. According to the Law of Conservation of Energy, the total amount of energy in the universe

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1 Directions: Please choose the best answer choice for each of the following questions. 1. Heating an object excites the surface molecules, causing them to give off infrared rays. is the transmission of electromagnetic rays through space. Radiation Convection Conduction Induction 2. Which of the following represents the correct order, from fastest to slowest, of the rate at which heat will conduct through different phases of matter? Gases- liquids-solids Solids- gases-liquids Solids- liquids- gases Gases-solids-liquid 3. According to the Law of Conservation of Energy, the total amount of energy in the universe remains constant changes constantly 4. Which energy transformation takes place in a working solar cell? chemical energy into potential energy chemical energy into electrical energy increases decreases solar energy into electrical energy solar energy into chemical energy 5. During the process of photosynthesis, plants absorb sunlight and convert carbon dioxide and water into sugar and oxygen. What is the basic energy transformation that takes place during photosynthesis? electrical energy to heat energy heat energy to electromagnetic energy chemical energy to electrical energy radient energy to chemical energy 6. Rainwater falling at higher elevations causes erosion as it flows downhill. Which form of energy in the water is responsible for soil erosion? chemical kinetic heat potential 7. A student heats the same amount of two different liquids over Bunsen burners. Each liquid is at room temperature when the student begins. If liquid 1 has a higher specific heat than liquid 2, then liquid 1 will evaporate sooner take longer to increase in temperature Condense over a longer period chemically break down at a faster rate 8. A ball is falling from a height under the force of gravity. Which energy transformation is taking place during the fall before the ball reaches the ground? Kinetic energy is changing into heat and sound energy. Potential energy is increasing, and kinetic energy is Potential energy is changing into heat and sound decreasing. energy. Kinetic energy is increasing, and potential energy is decreasing. 9. Burning a wooden match is an example of an exothermic reaction. Which of these processes occurs during most exothermic reactions? use of oxygen creation of gases release of heat production of sound Page 1

2 10. Electricity was transferred from a generator to an incandescent light bulb. After five minutes the bulb was still lit and also became very hot. Which BEST explains why the bulb became hot? The energy was converted into light and heat energy. The light energy given off by the bulb caused the bulb to heat up. The energy transferred from the generator was at too high an efficiency. The energy transferred from the generator was transferred at a very low efficiency. 11. Isabel studies a pendulum in a lab activity, as shown below. Which energy change occurs when the pendulum moves from point B to point A? Kinetic and potential energy both increase. Kinetic and potential energy both decrease. Kinetic energy converts into potential energy. Potential energy converts into kinetic energy. 12. Ms. Pierre explains to her class that in a hydroelectric power station, water is allowed to fall from a great height through a turbine. As a result, the blades of the turbine rotate and current is produced. Which sequence of energy transformation can be identified in Ms. Pierre s explanation? 13. Two different objects with the same mass are both heated to 100 degrees Celsius. Which of the two objects will change temperature the fastest? The object with the highest specific heat Both will change temperature at the same rate The object with the lowest specific heat Neither will change temperature. 14. Mark was playing with a spiral made of aluminum foil. He observed that the spiral twirled when he held it over a warm toaster that he just used and then unplugged. What is the reason for his observation? pull of gravity force from a magnetic field heat transfer by conduction formation of convection currents Page 2

3 15. Eric arranged materials for his experiment, as shown below. After heating the metal plate for some time, he observed that temperatures decreased from thermometer 1 to thermometer 4. Which reason BEST explains the variation in temperature? The metal plate is not radiating heat consistently. The metal plate is too small to transfer heat by convection. 16. The frying pan in the diagram below is made completely of iron. The temperature of the surroundings contributes to the variation in reading. A decrease in molecular motion from the hot end to the cold end causes a decrease in temperature. How does heat move from the bottom of the pan to the handle? Free electrons move from atom to atom. Heat flows through the empty space between atoms. Iron atoms transfer kinetic energy from atom to atom. Rapidly vibrating atoms move away from the source of heat. 17. Manuel is studying several different samples of gas. How can he find which gas sample has molecules with the highest average kinetic energy? by finding the temperature of each sample by finding the heat content of each sample 18. Which of these describes the movement of heat by convection? heat transfer from a stove burner and a pan hot fluid rising and cool fluid falling by finding the pressure and volume of each sample by finding the average molecular weight of each sample radiant heat energy moving through space hot water warming up a glass container 19. Stainless steel has a specific heat capacity of 0.5 J/g/K. How many joules of energy would be needed to raise 10 grams of stainless steel by 4 degrees Kelvin? Page 3

4 20. Naomi is investigating the properties of a solid material. It takes 120 joules to raise the temperature of 10 grams of the material by 5 degrees. What is the specific heat of the material? 21. An iron ball weighing was heated from to. How much heat energy did the iron ball gain? (The specific heat of iron is.) 22. In a coal burning power plant, coal is burned to heat water to steam in order to turn a turbine. The turbine generates power that is sent to homes and businesses. Order the energy transformations of the power plant. chemical, mechanical, electrical mechanical, chemical, electrical electrical, chemical, mechanical mechanical, electrical, chemical 23. Which of the following is the most accurate statement regarding the movement of heat through metal rods? all movement of heat requires some form of matter radiation conduction convection 24. If you hold a paper cup containing hot chocolate in your hand, thermal energy: does not flow flows from the hot chocolate to your hand flows from the air to the hot chocolate flows from your hand to the hot chocolate 25. Conduction can BEST be described as the transfer of energy by: waves traveling through empty space. fluids traveling through other fluids. gases expanding within a fluid medium particles colliding with their neighbors. 26. Which acceleration is produced by a 20 Newton force acting on a 5 kilogram object? Page 4

5 27. Which of these velocity-time graphs correctly represents the movement of a car with a constant acceleration? A B C D 28. A force is applied on two different objects. When it is applied to object A, the object has an acceleration of meters per second squared. When it is applied to object B, the object has an acceleration of meters per second squared. Which object has the larger mass? Object B with an acceleration of 6.0 m/s 2 Object A with an acceleration of 3.0 m/s 2 They have the same mass Not enough information to identify the largest mass. Page 5

6 29. The table below shows the velocity of a car at regular time intervals. Which of these conclusions can be drawn about the motion of the car? The car moves with a uniform velocity. The car moves with a uniform acceleration. The acceleration of the car increases with time. The rate of change of velocity decreases with time. 30. A truck starts from rest and moves with a constant acceleration. If the truck travels a distance of in, what is the truck s acceleration? 31. Which example illustrates Newton s first law? A soccer player kicks a ball. A rocket is launched into space using jet propulsion. A cannon moves backward when a cannonball is fired. A person not wearing a seatbelt lunges forward when a car suddenly stops. 32. Which term is defined as the tendency of an object to resist changes in motion? acceleration friction inertia velocity 33. The river shown below is flowing due east. The paper boat, carried by the force of the river s current, is also moving due east. Which of these winds could cause the paper boat to begin moving toward the northeast? a wind blowing west a wind blowing east a wind blowing south a wind blowing north Page 6

7 Directions: Review the content below and answer the questions that follow Force and Acceleration Clyde sets a trolley, a pulley, and some weights, as shown below, to perform experiments on applied force and the resulting motion. Experiment 1 Clyde begins the experiment by attaching an weight to the string. As the weight is attached, the trolley begins to move and hits the pulley in. Experiment 2 Clyde places a brick on the table in the line of motion of the trolley. As the the brick. Let us suppose that the force applied by the trolley on the brick is weight pulls the trolley, the trolley moves and hits newtons. Experiment 3 Clyde places the trolley in the middle of the table and attaches equal weights on both sides of the trolley. Experiment 4 Clyde places a ball in the trolley and repeats experiment 1 with a weight attached to the string. Experiment 5 Clyde removes the trolley from the experiment and uses the fixed pulley to lift a height of. block from the ground. The block is lifted to a 34. How would the acceleration produced by the trolley vary if a weight was attached to the string in addition to original weight in experiment 1? The acceleration would increase by half of the original value. The acceleration would decrease by half of the original value. The acceleration would increase by two times the original value. The acceleration would decrease by two times the original value. 35. Clyde performs an experiment similar to experiment 1 with two different trolleys, with masses of and, respectively. The same force is used to pull each trolley. If the acceleration produced on the trolley is, what is the acceleration Page 7

8 produced on the trolley? 36. What would be the nature of the motion of the trolley in experiment 3? The trolley would move back. The trolley would move forward. The trolley would not move in any direction. The trolley would move back and forth alternatively. 37. What is the amount of work done in experiment 5? 38. Which floor safe would require the greatest force to move because of its mass? safe 1 safe 2 safe 3 All 3 would be the same since all are at rest. 39. Carla studied the flight paths of four objects. She threw each object with the same arm motion while exerting the same amount of force. Which object had the greatest speed as it left Carla s hand? brick quarter baseball broomstick 40. A jockey has a mass of 50 kg. His horse has a mass of 450 kg. How much force is needed to accelerate both the jockey and the horse to 5 m/s 2? 100 N 250 N 2250 N 2500 N 41. Which of these would cause the LEAST acceleration? a 5-newton force acting on a 5-kilogram object a 10-newton force acting on a 5-kilogram object a 5-newton force acting on a 10-kilogram object a 10-newton force acting on a 10-kilogram object 42. A baseball player swings his bat and the bat strikes the ball with a force of 200 N. The ball does not push against the bat as it flies away. pushes against the bat with a force of 200 N. pushes against the bat with a force less than 200 N. pushes against the bat with a force greater than 200 N. Page 8

9 43. According to Newton s Third Law, the downward force of Earth s gravity affects all objects on Earth including bugs, rocks, humans, cars, and even the atmosphere. In all of these cases the Earth exerts an equal and opposite downward force on the objects. Earth exerts unequal but opposite downward force on the objects. objects exert an unequal but opposite upward force on the Earth. objects exert an equal and opposite upward force on the Earth. 44. According to Newton s Third Law of Motion, when a rocket is launched, which of the following occurs? The upward force on the rocket does not have any force on the exhaust gases. The upward force on the rocket equals the downward force on the exhaust gases. The upward force on the rocket is less than the downward force on the exhaust gases. The upward force on the rocket is greater than the downward force on the exhaust gases. 45. Jose likes to paddle his canoe on a river that runs through a state park. How does Newton s third law of motion apply as he paddles the canoe? The canoe moves forward because of the gravitational force. The canoe moves forward because of the buoyancy of the boat. The canoe moves forward when the water is pushed forward. The canoe moves forward when the water is pushed backward. 46. All objects thrown up in the air always fall back toward Earth. Which reason explains this statement? frictional force acting on the objects increased kinetic energy of the objects gravitational force acting on the objects decreased air pressure acting on the objects 47. Which of these is responsible for raindrops falling to the ground? low frictional force on the raindrops gravitational pull on the raindrops high kinetic energy of raindrops high density of raindrops 48. The table below shows the approximate weight of the same object when it is placed on three different celestial bodies in the solar system. What can be concluded about the mass and weight of this object? The weight of the object is different from its mass on all bodies in the solar system. The weight of the object decreases as its mass increases on different bodies in the solar system. The weight of the object increases as its mass decreases on different bodies in the solar system. The weight of the object remains the same, and its mass keeps changing on different bodies in the solar system. 49. Janet explains to her class that an object with a mass of weighs. Which statement does she use to explain this difference clearly? Mass is a measurement of an object s volume. Weight is a measurement of the pull of gravity on an object. Weight is a measurement of the amount of matter in an object. Mass is a measurement of the frictional force exerted on an object. Page 9

10 50. A force of is applied to drill a screw deep into a wall. What is the amount of work done? 0.1 joule 1.0 joule 10.0 joule joule 51. The figure below shows an arrangement of pulleys used to lift a - load. What is the mechanical advantage of the system if an effort of is required to lift the load? A man uses a lever to pick up a load positioned 1 meter from a fulcrum. If effort is applied 5 meters from the fulcrum, what is the mechanical advantage for this lever? A load is pushed a distance of 15 meters on an inclined plane. If the load is moved up a vertical distance of 3 meters, what is the mechanical advantage of the inclined plane? How much work is done when Jack uses a fixed pulley to move a 100-newton block 0.50 meter? 5 joules 50 joules 500 joules 5,000 joules Page 10